/**
 * Copyright (C) 2009 SC 4ViewSoft SRL
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package math.spbu.ru.historycharts.charts;

import math.spbu.ru.historycharts.model.XYMultipleSeriesDataset;
import math.spbu.ru.historycharts.renderer.PointStyle;
import math.spbu.ru.historycharts.renderer.SimpleSeriesRenderer;
import math.spbu.ru.historycharts.renderer.XYMultipleSeriesRenderer;
import math.spbu.ru.historycharts.renderer.XYSeriesRenderer;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Paint.Style;



/**
 * The line chart rendering class.
 */
public class LineChart extends XYChart {
    /**
     * The legend shape width.
     */
    private static final int SHAPE_WIDTH = 30;

    /**
     * Builds a new line chart instance.
     *
     * @param dataset  the multiple series dataset
     * @param renderer the multiple series renderer
     */
    public LineChart(XYMultipleSeriesDataset dataset, XYMultipleSeriesRenderer renderer) {
        super(dataset, renderer);
    }

    /**
     * The graphical representation of a series.
     *
     * @param canvas         the canvas to paint to
     * @param paint          the paint to be used for drawing
     * @param points         the array of points to be used for drawing the series
     * @param seriesRenderer the series renderer
     * @param yAxisValue     the minimum value of the y axis
     * @param seriesIndex    the index of the series currently being drawn
     */
    public void drawSeries(Canvas canvas, Paint paint, float[] points,
                           SimpleSeriesRenderer seriesRenderer, float yAxisValue, int seriesIndex) {
        int length = points.length;
        XYSeriesRenderer renderer = (XYSeriesRenderer) seriesRenderer;
        if (renderer.isFillBelowLine()) {
            paint.setColor(renderer.getFillBelowLineColor());
            int pLength = points.length;
            float[] fillPoints = new float[pLength + 4];
            System.arraycopy(points, 0, fillPoints, 0, length);
            fillPoints[0] = points[0] + 1;
            fillPoints[length] = fillPoints[length - 2];
            fillPoints[length + 1] = yAxisValue;
            fillPoints[length + 2] = fillPoints[0];
            fillPoints[length + 3] = fillPoints[length + 1];

            drawPath(canvas, fillPoints, paint, true);
            paint.setStyle(Style.FILL);
        }
        paint.setColor(seriesRenderer.getColor());
        paint.setStyle(Style.STROKE);
        drawPath(canvas, points, paint, false);
    }

    /**
     * Returns the legend shape width.
     *
     * @return the legend shape width
     */
    public int getLegendShapeWidth() {
        return SHAPE_WIDTH;
    }

    /**
     * The graphical representation of the legend shape.
     *
     * @param canvas   the canvas to paint to
     * @param renderer the series renderer
     * @param x        the x value of the point the shape should be drawn at
     * @param y        the y value of the point the shape should be drawn at
     * @param paint    the paint to be used for drawing
     */
    public void drawLegendShape(Canvas canvas, SimpleSeriesRenderer renderer, float x, float y,
                                Paint paint) {
        canvas.drawLine(x, y, x + SHAPE_WIDTH, y, paint);
    }

    /**
     * Returns if the chart should display the points as a certain shape.
     *
     * @param renderer the series renderer
     */
    public boolean isRenderPoints(SimpleSeriesRenderer renderer) {
        return ((XYSeriesRenderer) renderer).getPointStyle() != PointStyle.POINT;
    }
}
